Azo dye-forming system including a boric acid ester

ABSTRACT

THE RESISTANCE TO PREMATURE COUPLING AND THE DEVELOPMENT RATE OF TWO-COMPONENT DIAZOTYPE COMPOSITIONS I.E., AT LEAST ONE DIAZONIUM SALT AND AT LEAST ONE COUPLER COMPOUND) ARE ADVANTAGEOUSLY INCREASED BY THE INCLUSION THEREIN OF A BORIC ACID ESTER.

25, 1972 G. P. KASPER 3,679,421

AZO DYE-FORMING SYSTEM INCLUDING A BORIC ACID ESTER Filed Aug. 26, 1969D/AZOTYPE COMPOSITION INCLUDING A BOP/C ACID ESTER OIA Z0 TYPE 6 OMPOS/T/ON WITHOUT A BOP/C ACID E 5 T E I? "/0 COMPLETION OF DEVELOPMENT 0 I ll 1 DEVELOPMENT TIME SECONDS GEORGE P KASPEE INVENTOR.

BY Mk/k ATTORNEY United States Patent US. CI. 96-91 R 7 Claims ABSTRACTOF THE DISCLOSURE The resistance to premature coupling and thedevelopment rate of two-component diazotype compositions (i.e., at leastone diazonium salt and at least one coupler compound) are advantageouslyincreased by the inclusion therein of a boric acid ester.

This invention is related to photography and is concerned particularlywith novel, two-component diazotype compositions which provide increasedresistance to premature coupling upon storage and permit an increaseddevelopment rate.

Two-component diazotype reproduction media normally comprise a polymericmatrix containing at least one diazonium salt and at least one couplercompound which reacts with the diazonium salt, typically in an alkalinemedium, to form an azo dye. In addition, there can be present variousother additives, such as ultraviolet absor bers, stabilizers to preventpremature coupling of the diazonium salt and the coupler as well asadditional known addenda. These diazotype compositions or azodye-forming systems have been employed generally as duplicating media.Their use typically involves an imagewise exposure to activatingradiation, e.g., light, through an original, whereby the transmittedlight decomposes the diazonium salt. After exposure the iilm is usuallytreated with a basic medium, such as aqueous ammonia vapor, to promotecoupling of the undecomposed diazonium salt and coupler compound,thereby forming an azo dye in the unexposed areas to provide a positiveimage corresponding to that of the original.

Two disadvantages heretofore associated with diazotype reproductionmedia are that such media tend towards instability causing undesirablepre-coupling upon storage, and that the processing times for imagedevelopment are often unduly long. (It is known that certain organicacids contained in the media prevent pre-coupling of the diazonium saltand the coupler compound before development of the desired image.Likewise, it is known that certain addenda compounds accelerate thedevelopment rate. However, many modifying chemical addenda candeleteriously affect photographic properties. Also, it has beennecessary heretofore to incorporate at least two distinct compounds topromote storage stability and to accelerate development rate of adiazotype composition.

Accordingly, it is an object of this invention to provide a newlight-sensitive azo dye-forming system.

Another object of the present invention is to provide a novellight-sensitive azo dye-forming system which exhibits both an increasedresistance to premature coupling and an increased development rate.

Still an additional object of the instant invention is to provide a newlight-sensitive azo dye-forming system containing a boric acid ester topromote increased resistance to premature coupling and an increaseddevelop ment rate.

Yet another object of the present invention is to provide a noveltwo-component diazotype composition containing a boric acid ester bothto inhibit premature coupling and to promote rapid development.

ice

These and other objects of the present invention will becomeincreasingly apparent from a reading of the following specification andappended claims.

The objects of this invention are accomplished with a diazotypecomposition which is useful as an image reproduction medium and whichincludes at least one lightsensitive diazonium salt, at least onecoupler compound which can react with the diazonium salt to form an azodye, as a combined precoupling inhibitor-development accelerator, atleast one boric acid ester.

The boric acid esters used in the present diazonium compositions includethe esterification products of boric acid and at least one hydroxylatedorganic compound such as an alcohol which is advantageously an aliphaticor aromatic monoor polyhydroxylic compound with monoand dihydroxyalcohols and glycols being favored. The boric acid esters useful hereincan be desirably substituted, but it is preferred that they aresubstituted with other than highly basic substituents such as alkalinenitrogen-containing radicals, so as to preserve the advantageous acidiccharacter of the diazotype composition prior to the desired time ofimage development, thereby heightening the precoupling restraintpromoted by the subject boric acid esters.

Especially advantageous boric acid esters utilized herein are boric acidtriesters of monohydn'c alcohols. Exemplary triesters include thosehaving alkyl ester groups such as cycloalkyl and aliphatic alkyl groupsincluding substituted aliphatic alkyl groups such as aralkyl groups aswell as those having aryl ester groups. The ester groups attached to anyboric acid molecule can be the same or different and can be composed ofvarious substituent ester groups of the types mentioned immediatelyhereinabove. Especially useful ester groups include cycloalkyl radicalshaving from 4 to 6 carbon atoms in the ring nucleus, aliphatic alkylradicals having from .1 to 8 carbon atoms in an alkyl chain which can besubstituted with radicals including carbon atoms additional to those ofthe 1 to 8 carbon aliphatic alkyl chain (e.g. aralkyl radicals) and arylradicals such as phenyl or n'aphthyl radicals. It is understood that thenoted cycloalkyl, aliphatic alkyl and aryl ester group radicals arejoined to the boric acid moiety through an oxygen linkage.

Preferred boric acid esters include such compounds as:

a trimethyl boric acid ester,

a dimethylethyl boric acid ester,

a triethyl boric acid ester,

a tripropyl boric acid ester,

a triphenyl boric acid ester,

3. tri(p-chlorophenyl) boric acid ester, a trinaphthyl boric acid ester,

a tricyclohexyl boric acid ester,

a tri(p-tolyl) boric acid ester, and

a triphenethyl boric acid ester.

The boric acid esters which are useful in this invention areadvantageously incorporated into diazotype compositions in an amount upto 25 parts by weight per parts by weight of polymeric matrix andpreferably between about 5 and 10 parts by weight per 100 parts byweight of polymeric matrix.

The diazotype compositions utilized herein typically include a diazoniumsalt and at least one coupler compound which can react with thediazonium salt to form an azo dye. Advantageous diazonium salts includebenzene diazonium salts such as those having the formula:

wherein M is either:

(1) a hydrogen atom, (2) a halogen atom, (3) an aryl radical, (4) anamino radical including substituted amino radicals which can be cyclicradicals including the amino nitrogen atom and other hetero atoms suchas oxygen, sulfur, nitrogen, etc., (5) a rnercapto radical, or (6) analkyl or aryl thioether radical, and

acid anion.

These compounds can also be substituted on one or more of the nuclearbenzene carbons with, for example, at least one of either a halogenatom, an aliphatic alkyl radical, an alkoxy radical, an acyl radical, acarbamyl radical, a carboxyl radical or a nitro radical. Aliphatic alkylradicals are defined herein to include straight and branched chain alkylradicals having from 1 to 8 carbon atoms such as methyl, ethyl,isopropyl, tertbutyl, n-amy], octyl and the like.

Particularly useful diazonium salts include p-aminobenzenediazoniumsalts having the formula as described above wherein M is either an aminoradical including substituted amino radicals or a thioether radical suchas described above, and wherein the benzene nucleus is unsubstituted orsubstituted in at least one of the 2-position and the 5-position witheither an aliphatic alkyl radical or an alkoxy radical. This class ofuseful diazonium salts can be represented by the formula:

wherein:

(1) D is either a sulfur atom or a radical having the formula NR (2) Rwhen taken alone, is either a hydrogen atom when D is NR or a loweraliphatic alkyl radical, a lower alkoxy radical, an acyl radical havingthe formula wherein T is either an aryl radical or an alkyl radical asdescribed elsewhere herein, or a phenyl radical when D is either asulfur atom or NR,

(3) R, when taken alone, is either a hydrogen atom, a

lower alkyl radical or a lower alkoxy radical,

(4) R and R when taken together, complete a divalent radical having theformula:

Preferred p-aminobenzene diazonium salts include substitutedaminobenzene diazonium salts having the formula:

4 wherein:

( 1) each of R and R, when taken alone, is a lower alkyl radical,

(2) R and R when taken together, are the number of The most preferredbenzene diazonium salts are the fluoroborate salts wherein:

(1) R and R are alkoxy radicals when R and R complete a morpholinoradical, and

(2) R and R are each a hydrogen atom when R and R are each a lower alkylradical.

Illustrative of the subject diazonium salts are such compounds as thesalts of 1-diazo-2,S-dimethoxybenzene; l-diazo-2,5-diethoxybenzene;l-diazo-4-chloro-2,S-diethoxybenzene; 4idiazo-2,5-dimethoxybiphenyl;4-diazo-2,5,4'-triethoxybiphenyl; 1-diazo-4-dimethylaminobenzene;l-diazo-4-(diethoxyamino)benzene; 1-djazo-4- [bis(hydroxypropyl)amino1benzene; l-diazol(N-methyl-N-allylamino)benzene;1-diazo-4-(diamy1amino)benzene; l-diazo-4-(oxazolidino)benzene;1-diazo-4-'(cyclohexylamino)benzene; l-diazo-4-(9-carbaz1olyl)benzene;1-diazo-4.-(dihydroxyethylarnino)-3-methylbenzene;1-diazo-4-dimethylamino-3-methylbenzene;1-diazo-2-methyl-4-(N-methyl-N-hydroxypropylamino) benzene;1-diaZo-4-dimethylamino-3-ethoxybenzene;1-diazo-4-diethylamino-3-chlorobenzene;1-diazo-2-carboxy-4-dimethylaminobenzene; 1-diazo-3- (2-hydroxyethoxy)-4-pyrrolidinobenzene; 1-diazo-2,5-diethoxy-4 acetoxyaminobenzene;1-diazo-4-methylamino-3-ethoxy-6-chlorobenzene; 1-diazo-2,5-dichloro-4-benzylaminobenzene; 1-diazo-4-phenylaminobenzene;l-diazo-4-morpholinobenzene; 1-diazo-4-morpholino-3-methoxybenzene;1-diazo-4-morpholino-2,S-dimethoxybenzene;1-diazo-4-morpholino-2-ethoxy-S-methoxybenzene;1-diazo-4-morpholino-2,S-dibutoxybenzene;1-diazo-2,S-diethoxy-4-benzoylaminobenzene;1-diazo-2,5-dibutoxy-4-benzoylaminobenzene;l-diazo-4-ethylmercapto-2,5-diethoxybenzene;1-diazo-4-tolylmencapto-2,5-diethoxybenzene and the like,

as well as mixtures thereof.

Azo dye couplers which can be reacted with the diazonium salt to form anazo dye include a wide variety of chemical species such as thosedisclosed by Kosar, Light-Sensitive Systems, John Wiley & Sons, Inc.,New York 1965), pp. 220-240. Phenolic couplers are preferred, however,with particularly preferred classes including:

(1) As blue couplers, 2-hydroxy-3-naphthanilides having the formula:

wherein R is a phenyl radical, and preferably a phenyl radicalsubstituted with at least one of either a lower alkyl radical or a loweralkoxy radical or a halogen atom;

(2) As blue couplers, ortho naphthalenediols,

(3) As yellow couplers, l-hydroxy-Z-naphthamides having the formula:

(III

wherein:

NH 0 R wherein R is either an alkyl radical or an alkoxy radical and Ris an aliphatic alkyl radical, an aryl radical, an aralkyl radical or anaralkoxy radical.

Illustrative of the subject couplers are such compounds as for example,

2-hydroxy-3-naphthanilide; 2-hydroxy-2-methyl-3-naphthanilide;Z-hydroxy-Z,2'-dimethoxy-5-chloro-3-naphthanilide;2-hydroxy-2-dimethoxy-3-naphthanilide;2-hydroxy-2',5-dimethoxy-4'-chloro-3-naphthanilide;2-hydroxy-1'-naphthyl-3-naphthanilide; Z-hydroxy-'-naphthyl-3-naphthanilide; 2-hydroxy-4'-chloro-3-naphthanilide;2-hydroxy-3-naphthanilide; 2-hydroxy-2',5'-dimethoxy-3-naphthanilide;2-hydroxy-2',4'-dimethyl-B-naphthanilide; 2,3-naphthalene diol;l-hydroxy-Z-naphthamide; N-methyl-l-hydroxy-Z-naphthamide;N-butyl-l-hydroxy-Z-naphthamide; N-octadecyl-l-hydroxy-Z-naphthamide;N-phenyl-l-hydroxy-Z-naphthamide;N-methyl-N-phenyl-l-hydroxy-Z-naphthamide;N-(Z-tetradecyloxyphenyl)-1-hydroxy-2-naphthamide;N-[4(2,4-di-tert-amylphenoxy)butyl]-l-hydroxy-2- naphthamide;l-hydroxy-Z-naphthopiperidide;N-(3,5-dicarboxyphenyl)-N-ethyl-l-hydroxy-2-naphthamide;N,N-dibenzyl-l-hydroxy-2-naphthamide;N-(Z-chlorophenyl)-l-hydroxy-2-naphthamide;N-(4-methoxyphenyl)-l-hydroxy-2-naphthamide;1-hydroxy-2-naphthopiperidide; l,3-bis( l-hydroxy-2-naphthamidobenzene)Z-acetamido-S-methylphenol; 2-acetamido-5-pentadecylphenyl;Z-butyramido-S-methylphenol;2-(2,4di-tert-amylphenoxyacetamido)-5-methy1phenol;Z-benzamido-S-methylphenol and the like, as well as mixtures thereof.

In addition to the various alkyl, alkoxy and aryl radicals describedherein, it is noted that lower aliphatic alkyl and alkoxy radicals aredeemed to refer to aliphatic alkyl and alkoxy radicals having from 1 to4 carbon atoms such as methyl, ethyl, propyl, isopropyl, isobutyl,tert-butyl and like alkyl radicals as well as alkoxy radicals such asmethoxy, ethoxy, propoxy, tert-butoxy and the like.

For ease of coating and stability of the coated layer, the diazotypecomposition is generally dispersed in a polymeric matrix such as thosedescribed hereinbelow, conventionally in an amount of from about 20 toabout 40 parts by weight per parts of matrix polymer.

In addition to the dye-forming components and boric acid esters of thisinvention, the diazotype composition can contain and usually doescontain other additives such as ultraviolet absorbers, stabilizers andthe like to advantageously modify its photographic and chemicalproperties. A preferred class of additives includes the known acidstabilizers which operate to prevent premature coupling of the diazoniumsalt and coupler compound. These acid stabilizers include organic acidssuch as S-sulfosalicylic acid and the like. In general, an organic acidstabilizer is preferably present in all of the diazotype reproductionmedia of this invention, with the amount normally varying from about 1part to about 6, and preferably from about 2 to about 5 parts by weightper 100 parts of polymeric matrix. Additionally, metal salts such aszinc chloride can also be present as a development accelerator or dyebrightener, generally in an amount of from about 0.5 to about 1.5 partsby weight per 100 parts of matrix polymer.

Another, and especially desirable, class of additives for diazotypecompositions comprises hindered phenols containing in the 2-positioneither an alkyl or a cycloalkyl radical and in the 4-position an alkylradical, an alkoxy radical, a hydroxyl radical or a thioether radical,which with the hindered phenolic moiety completes a hinderedbisthiophenol and more generally a symmetrical bisthiophenol. Thesehindered phenols restrain fading of the developed azo dye image. Suchadvantageous hindered phenols are described in detail in the copendingUS. patent application Ser. No. 663,470, filed July 31, 1967, now PatentNo. 3,591,381.

The diazotype compositions, including all supplemental addenda, aretypically carried in a film-forming hydrophobic polymeric matrix orhinder when preparing photographic elements, both for ease of coatingand physical stability of the resultant light-sensitive layer.Advantageous matrix polymers include a wide variety of polymericsubstances such as, for example, cellulosic ethers such as ethylcellulose, butyl cellulose as well as cellulose esters such as celluloseacetate, cellulose triacetate, cellulose propionate, cellulose acetatepropionate, cellulose butyrate and cellulose acetate butyrate; vinylpolymers such as poly(vinyl acetate), poly(vinylidene chloride), poly(vinyl butyral), copolymers of vinyl chloride and vinyl acetate,polystyrenes, poly(methyl methacrylate), copolymers of alkylacrylatesand acrylic acid, etc.; polyesters such as the esterification product ofp-cyclohexanedicarboxylic acid and2,2,4,4-tetramethylcyclobutane-1,3-diol, as well as additional polymerssuch as polyphenylene oxides, terpolymers of ethylene glycol,isophthalic acid and terephthalic acid and terpolymers of p-cyclohexanedicarboxylic acid, isophthalic acid and cyclohexylenebismethanol.

Photographic elements utilizing the light-sensitive diazotypecompositions of this invention are conveniently prepared by coating sucha composition onto a support material by means such as immersion, flowcoating, whirl coating, brushing, doctor blade coating, hopper coatingand the like to prepare a light-sensitive layer. Advantageous supportmaterials include conventional photographic film base materials, forexample, cellulose esters such as cellulose acetate, cellulosetriacetate, cellulose acetate butyrate, etc., poly a-olefins such aspolyethylene and polypropylene, polyesters such as poly(ethyleneterephthalate), polystyrenes, polycarbonates, as well as metals such aszinc and aluminum and paper including polyethylene and polypropylenecoated papers. Other support materials that are suitable for use hereinare known in the art.

Coating is typically by solvent coating means, since it offers thepotential for rapid, convenient, continuous operation. Coatingis'eflected by first dissolving the photographic image-formingcomposition in a suitable solvent, along with a matrix polymer ifdesired. Exemplary matrix polymers are described hereinabove. Thecoating solution conventionally contains from about to about 20 weightpercent solids, and preferably from about 8 to about 15 percent solids.In that solution, if a matrix polymer is utilized, the photographicimage-forming components are typically included in an amount of fromabout 20 to about 50 parts by weight per 100 parts of polymeric binder,with concentrations in the range of from about 25 to about 45 parts per100 parts of matrix polymer being preferred. Wider variations arepossible where desired, but .the abovementioned ratios are typical formost conventional preparations. After coating by such means as whirlcoating, brushing, doctor blade coating, hopper coating or the like,typically at a Wet thickness of from about 25 microns to about 125microns, the coated material is dried to prepare a compositephotographic element of this invention.

The diazotype compositions of this invention, including a boric acidester such as those described herein, are advantageouslyrapidlyprocessibleunder a wide variety of proc s sing conditions. Moreover,they exhibit significant resistance to undesirable precoupling, even atelevated temperatures and under high humidity conditions, thisresistance being maintained for long periods of time (e.g. 6 months to 1year).

After the light-sensitive layer has dried, the resultant elements can beimagewise exposed and developed to prepare a positive azo dye imagecorresponding'to the original. Exposure is typically to a light sourcerich in ultraviolet rays, such as a mercury arc lamp, a photoflood lampor the like. Image development is conveniently accomplished bycontacting the exposed element with an alkaline medium such as moistammonia vapor at ambient pressure or high pressure anhydrous ammoniagas, which promotes the reaction ofdiazonium salt and coupler compoundto form an azo dye image. No further image stabilization is necessary.

The following examples are included for a further understanding of theinvention.

EXAMPLE 1 -A light-sensitive diazotype composition is preparedcontaining the following ingredients:

The composition is coated using a doctor blade onto a subbedpoly(ethylene terephthalate) support material to prepare a photographicelement. After drying, the thickness of the light-sensitive layer isabout 7.5 microns. Portions of the element so prepared are stored underdark conditions at 21 C. and 100% relative humidity for a Alight-sensitive diazotype composition containing the followingingredients is prepared:

G. Cellulose acetate-butyrate 7.220 Acetone 49.280 Methanol 19.420Methyl Cellosolve 7.520 5-su1fosalicylic acid 0.306 2,5 dibutoxy 1morpholinobenzene diazonium sulfate with 20% tartaric acid 1.5302'-methoxy-3-hydroxy-2-naphathanilide 0.7881-hydroxy-2-naphthopiperidide 0.497 Propylene oxide 0.050

Additive A as in Example 1 12.620 Tricyclohexyl boric acid ester 0.769

The composition is coated using a doctor blade apparatus onto a subbedpoly(ethylene terephthalate) support to prepare a photographic element.After drying, the lightsensitive layer has a thickness of about 7.5microns. Portions of this element are then stored under dark conditionsat 38 C. and relative humidity for a period of hours. Minimum density ofthe unexposed portions rises by 0.38 after the storage period. Densitymeasurements are obtained as in Example 1.

EXAMPLE 4 A photographic element is prepared according to the procedureof Example 3, except that tricyclohexyl boric acid ester is omitted fromthe diazotype composition. Af-

ter storage of samples as in Example 3, the minimum density rises to0.51, density measurements being obtained as in Example 1.

EXAMPLE 5 The unexposed photographic element portions of Examples 1, 2,3 and 4 are processed by treatment with anhydrous ammonia gas at atemperature of 55 C. in a General Aniline and Film Ozalid JuniorOzamatic Processor. The development rate of the portions from Examples 1and 3 (containing a boric acid ester) is about twice as rapid as thatfor the portions from Examples 2 and 4 (boric acid ester omitted).Comparative development rates for the photographic elements of Examples1 and 2 are summarized below in tabular form, the rates being expressedin percent of developed density as a function of time.

Percent completion of development l 1 Percent of maximum developabledensity.

Comparative results are obtained with a comparison of elements fromExamples 3 and 4. A comparison of the results appearing in the abovetable is graphically presented in the accompanying drawing. In thegraph, the vertical axis is calibrated for a percentage of the maximumvisible difiuse density obtainable in a completely developed element.The horizontal axis is calibrated in seconds corresponding to thedevelopment time of each element. As indicated on the graph, the lowerplotted curve indicates the development rate of a diazotype compositionwhich does not contain a boric acid ester. The upper plotted curveindicates the increased development rate obtained with a like diazotypecomposition, but with tricyclohexyl boric acid ester added as a combinedpre-coupling inhibitor, development accelerator. It is seen by referenceto the graph that the rate of development with the boric acid esterpresent is significantly accelerated with developed density beingincreased by a factor of about 2.5 at 24 seconds development time.

EXAMPLE 6 The procedures of Examples 1, 2, 3, 4 and 5 are repeated inthree separate sets, except that in those elements containing a boricacid ester, the following esters are used in lieu of tricyclohexyl boricacid ester.

Set 1triethyl boric acid ester, Set Z-triphenyl boric acid ester, Set3tri-p-chlorophenyl boric acid ester.

Similar results are obtained.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be eflected within the spirit and scopeof the invention.

I claim:

1. A diazotype composition consisting essentially of a light-sensitivediazonium salt, a coupler compound which can react with said diazoniumsalt to form an azo dye, a film-forming, hydrophobic polymeric binder,an acidic stabilizer and, as a combined precouplinginhibitor-development accelerator, a triester of boric acid and amonohydric alcohol.

2. A diazotype composition as described in claim 1 wherein said boricacid ester is present in an amount of up to about 25 parts by weight per100 parts by weight of said hydrophobic polymeric binder.

3. A diazotype composition as described in claim 1 wherein said boricacid ester is present in an amount ranging from 5 to parts by weight per100 parts by weight of said hydrophobic polymeric binder.

4. A diazotype composition as described in claim 1 wherein the boricacid triester is selected from the group consisting of trialiphaticalkyl boric acid esters, triaryl boric acid esters and tricycloalkylboric acid esters.

5. A diazotype composition consisting essentially of a film-forming,hydrophobic polymeric matrix containing therein a light-sensitivediazonium salt, a coupler compound which can react with said diazoniumsalt to form an azo dye, an acidic stabilizer and as a combinedprecoupling inhibitor-development accelerator, a boric acid triesterselected from the group consisting of:

(a) trialiphatic alkyl boric acid esters wherein the alkyl moiety hasfrom 1 to 8 carbon atoms,

(b) triaryl boric acid esters wherein the aryl moiety is selected fromthe group consisting of a phenyl radical and a naphthyl radical, and

(c) tricycloalkyl boric acid esters having from 4 to 6 nuclear carbonatoms in the cycloalkyl ring.

6. A diazotype composition as described in claim 5 wherein the boricacid triester is selected from the group consisting of a trimethyl boricacid ester, a triethyl boric acid ester, a tripropyl boric acid ester, atriphenyl boric acid ester, and a tricyclohexyl boric acid ester.

7. A diazotype composition consisting essentially of a film-forming,hydrophobic polymeric matrix containing therein a light-sensitivediazonium salt, a coupler compound which can react with said diazoniumsalt to form an azo dye, an acidic stabilizer and, as a combinedprecoupling inhibitor-development accelerator, a tricyclohexyl boricacid ester in an amount ranging from 5 to 10 parts by weight per 100parts by weight of said polymeric matrix.

References Cited UNITED STATES PATENTS 1,758,676 5/1930 Schmidt et al.96-91 3,294,542 12/1966 Sus et al. 96-91 3,362,825 1/1968 Moskowitz etal. 96-91 X 3,386,827 6/1968 Aebi et al 96-49 X 3,409,434 11/ 1968Landberge et al 96-75 3,567,453 3/1971 Borden 96-91 FOREIGN PATENTS1,552,166 11/1968 France 96-75 OTHER REFERENCES Muller, P.: Precoatingof Diazotype Paper, Tappi, August 1965, pp. 55A, 56A, 57A, 58A and 59A.

CHARLES L. BOWERS, JR., Primary Examiner U.S. Cl. X.R. 96-49,

"H050 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.$679421 Dat d July 1 972 Inventor(s) George P. Kasper I It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 2, line 9, dye, as" should read ---dye d,

Column 3, line 1! "acid anion" should read ---Z is an acid anion---.

Signed and sealed this 27th day of May 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officerand Trademarks

